Fabrication of alginate@silver nanoparticles (Alg@AgNPs) bionanocomposite for the sequestration of crystal violet dye from aqueous solution.

In the present study, alginate@silver nanoparticles (Alg@AgNPs) bionanocomposite has been fabricated successfully and further explored for the removal of crystal violet (CV) dye from the aqueous solution. The surface morphology of the (Alg@AgNPs) bionanocomposite was characterized by various modern analytical techniques such as SEM-EDX, TEM, FTIR and XRD. The maximum adsorption was observed at optimum condition of (pH 7, adsorbent dose 0.01 g, equilibrium time 240 min and initial concentration 20 mg L−1). The maximum monolayer adsorption capacity was found to be 186.93 mg g−1 at 30 °C. The experimental data were further validated by various isotherm models and on the basis of highest correlation coefficient (R2, 0.99), Langmuir model was found to be best fitted model. Pseudo-second order kinetic model obeyed best for the experimental data with a highest correlation coefficient (R2, 0.99) at all studied temperature. In thermodynamic studies, the positive value of enthalpy change (∆ H 0 ) and entropy change (∆ S 0 ) confirmed the process to be endothermic and spontaneous in nature. Desorption studies shows that 83 % of the adsorbed CV can be desorbed in first cycle and can be regenerated up to 4th cycle effectively with 0.1 M HCl. Therefore, (Alg@AgNPs) bionanocomposite could be harnessed as a potential adsorbent for the removal of hazardous CV dye from the waste water. • Alginate@silver nanoparticles (Alg@AgNPs) bionanocomposite has been fabricated successfully. • The maximum monolayer adsorption capacity was found to be 186.93 mg g−1 at 30 °C. • Langmuir model was found to be best-fitted model. • Desorption data showed that above 83 % of CV by using 0.1 M HCl could be desorbed in a first cycle. [ABSTRACT FROM AUTHOR]